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Common Causes of Slow External and USB Flash Drive Performance and Data Transfer Rates


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Description


Poor or slow speeds can be caused by:

  • Host device port speed.
  • Format and file system.
  • Directory with lots of small files.
  • Deeply nested directory.
  • USB cable too long.
  • Not enough free space on the drive.
  • Connected to slower USB port.
  • The host does not have enough cache.
  • The cache is not optimized.
  • To many background programs.
  • Multiple connections to the computer.
  • Outdated drivers.


Resolution



USB Standard and Speeds


Version USB Interface Speeds Ports
SUPERSPEED USB 20Gbps
USB 3.2 (Gen 2x2)
20 Gb/s
(2500 MB/s)
USB Type-C, USB Type-A, etc.
SUPERSPEED USB 10Gbps
USB 3.2 (Gen 2)USB 3.1 (Gen 2)
10 Gb/s
(1250 MB/s)
USB Type-C, USB Type-A, etc.
SUPERSPEED
USB 3.2 (Gen 1)USB 3.1 (Gen 1)USB 3.0
5 Gb/s
(625 MB/s)
USB Type-C, USB Type-A, etc.
HI-SPEED
USB 2.0
480 Mb/s
(60 MB/s)
USB Type C, USB Type-A, etc.
USB 1.1 12 Mb/s
(1.5 MB/s)
USB Type-A, USB Type-B, etc.

Need more help?
Answer ID 5043: USB Interface Standards and Theorectical Speeds



Host Device USB-C Performance Specs

The speed of a drive depends on the port used.
Some systems have USB-C ports that work with different USB drives.
Solution: Check the host device to confirm specs of the USB-C port.



Performance Best Practices


  • Directory and File Sizes (Lots of small files)

The total amount of data on a disk and the size of each file can result in slow speeds.
Information: A large number of files saved in a single directory will transfer faster than the same number of files spread across multiple directories.

1 TB of large files will transfer much faster than 1 TB of millions of small files.
Use large ISO images to test read/write speeds.


  • Windows and macOS File System

Drives are formatted as NTFS, FAT32, exFAT and HSF+. File systems like NTFS on Windows and APFS on macOS perform better than exFAT, FAT32 and HSF+
Solution: Format the drive with the native OS file system.





Turn on write caching.

  1. Connect the drive.

  2. Press the Windows Key + X.
    Click Device Manager.

  3. Expand Disk Drives.
    Right-click the drive.
    Click Properties.


  4. Click Policies.
    Click Better performance.
    Click Enable write caching on the device.
    Click OK.


  • Windows 10 Real Time Protection

Doing a scan with this tool may cause slow speeds.
Solution: For a short time disable this tool.

Need more help?
Microsoft Article: Turn off antivirus protection in Windows Security


  • Connect to a Different Computer

Slow speed may be caused by the computer.
Solution: Test the drive on another one.


  • USB Hubs and Extension Cables

These can slow the drive speed.
Solution: Connect the drive directly into the system.


  • USB Port and Cable

Slow speeds can be caused by plugging into a slow or faulty USB port.
Solution:Use a high quality USB cable.


  • Confirm USB Type used by USB-C Port
  • Different types of USB use the USB-C port.
    Solution:Confirm USB-C speeds offered by the systems USB-C port.
    Contact the computer or motherboard maker for support.


  • Drive Space Available
  • Performance can decrease when drives are close to capacity.
    Solution: Make sure the drive has 10% to 15% space free for best results.


  • Laptops and Portable Computers

Make sure the computer has at least a 75% charged battery or is plugged in.
Solution: Adjust the power mode or Energy Saver Settings.


  • System Memory

Small amounts of memory may not have enough resources to process data. This can result in slow backups.
Solution: Stop apps and software that use high memory.


  • Computer in use during Speed Tests

Using the computer when running a speed test can use higher than normal CPU and memory.
Solution: DO NOT use the computer during these tests.


  • Fragmented Disk

This may cause slow disk read.
Solution: Defragment the disk.

Need more help?


  • Anti-Virus, Anti-Malware and End Point Protection Software

These tools scan incoming TCP/UDP packets which cause slower data transfer rates.
Solution: For a short time stop these softwares when moving data.


  • Infected Computer

A computer with virus or malware may cause slow speeds.
Solution: Make sure that the system is virus, trojan, and malware free.


  • RAID 0 vs RAID 1

RAID 0 offers the fastest read/write speeds but does not provide data protection like RAID 1.
Solution: Configure a device as RAID 0 for the best speeds.


  • CPU (32 bit vs 64 bit)

Older 32 bit CPU systems may not have the power to handle modern technology.
Solution: Stop apps and software that use high CPU and memory.


  • Outdated Motherboard Chipset or Drivers
  • These can affect system speeds.
    Solution: Make sure that the motherboard chipset and drivers are up to date.
    Contact the computer or motherboard maker for support.



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Details
Answer ID 17047
Published 08/20/2018 02:25 AM
Updated 03/29/2024 07:25 AM

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